It is common practice to print portions of a newspaper, called inserts, and to store these portions prior to collating the newspaper for delivery. It is equally common practice to print portions of a book, magazine, etc. called signatures, and to store these portions prior to collating.
Prior U.S. Pat. No. 4,538,511, to James C. Wise, assigned to the assignee of the present application, entitled "Signature Handling Apparatus", discloses a system for stacking signatures. A transfer vehicle is movable to the stacker to clamp onto a stack and transfer that stack to an adjacent tying station where the stack is tied to form a log or bundle. The transfer vehicle maintains positive engagement with the stack as it moves the stack from the tying station to a stack-delivery station.
Related embodiments of the system of the '511 patent are disclosed in prior U.S. Pat. No. 4,541,763 (Chandhoke et al.), entitled "Apparatus for Forming a Stack of Signatures". This patent is also assigned to the assignee of the present application.
In prior U.S. Pat. No. 4,498,381, to Frank H. Convey, Jr., assigned to the assignee of the present application, there is disclosed a further embodiment of the system of the '511 patent in which there is provided a clamping mechanism capable of bringing end boards to the stacker, and depositing the end boards on the stack as the clamping mechanism engages a stack. The clamping mechanism also has independently movable clamp members that can move to different coextants in applying pressure to different portions of a stack of signatures during the clamping process.
Also in the prior art is U.S. Pat. No. 4,462,735 to Bain et al., which discloses a system for handling newspapers whereby a reserve supply of newspapers can be maintained capable of compensating for unintentional shutdown of a printing press. In the '735 patent, an endless conveyor has carriers adapted to travel about the pathway of the conveyor and to removably support newspaper containers. A pair of spaced transfer conveyors operatively associated with the endless conveyor are adapted to sequentially receive and then return the containers to the endless conveyor. On one transfer conveyor the containers are positioned by an indexing member at a location for receiving a stack of newspapers, and on the other transfer conveyor the containers are indexed to a position where the newspapers are unloaded for further processing.
In co-pending application Ser. No. 261,394, filed Oct. 24, 1988, by Robert A. Bryson, Sr., assigned to the assignee of the present application, there is disclosed an improved handling system for building and handling stacks of flat printed products wherein containers which are used to transport the stacks of printed products are each comprised of a plurality of individual cells, each cell being adapted to accommodate a single stack.